Get a general. physical exam to r/o obvious causes--diet, weight, circulation, allergies and other possible culprits. Panic w/o physical causes is a psychological problem, so go see a mental health pro. Learn all you can about anxiety. it has a cause and 33 known sx's. Here's a place to start:
http://www.psychologyproductsandservices.com/page2.html.

Check Thyroid. Among other things these are all potential symptoms of hypothyroidism and if your thyroid function has not been checked it should be. If it has you should also have iron studies done. The list of potential reasons is extensive, but this is a great start.

Fatigue. Take some time off fro your work. Make a day schedule and stick to it.
Early in the morning in your bed, meditate on Universal God for 5 minutes (longer is better) irrespective of your religion. Thank Him for everything such as life, food, space to live, family, nature, water, air etc. Drink a glass of water.Go for a walk. Eat good breakfast. Talk to someone whom you trust. Watch T.V. whatever you.